Invasive Species Research Science for Detection, Containment, and Control

Invasive species research within the U.S. Geological Survey’s (USGS) Ecosystems Mission Area (EMA) focuses on invasive organisms throughout the United States. USGS scientists work with partners in the Department of the Interior (DOI), other Federal, State and Territorial agencies, Tribes, industry, and agriculture to provide the information needed to help solve problems posed by these invaders. Key components of USGS invasive species science include the development of novel prevention, prediction, early detection, containment, and control tools.

Invasive Species Facts USGS EMA Areas of Emphasis

• Invasive species are alien species whose introduction does • Preventing establishment and further spread of Asian carps in or is likely to cause economic or environmental harm, or the Great Lakes, Upper Mississippi, and Ohio River Basins harm to human health. • Control of sea lamprey (Petromyzon marinus) in the • Invasive species adversely affect every State, Territory, and Great Lakes Tribe in the Nation, including urban centers and wilderness • Support for brown treesnake (BTS, Boiga irregularis) areas. control on Guam and regional Pacific Island biosecurity • Increased global travel and trade provide pathways for both • Developing tools to address Rapid ʻOhiʻa Death (ROD, intentional and unintentional introductions of invasive species. Ceratocystis lukuohia and huliohia) in Hawaii (an introduced chytrid fungus infecting ʻOhiʻa, a native Hawaiian • Every year, harm caused by invasive species costs govern- tree species) ments, industries, and private citizens substantial economic losses potentially reaching into the billions of dollars. • Development of control and monitoring techniques for Burmese python (Python bivittatus), black and white tegu • The costs of battling invasive species impact farmers, (Tupinambis merianae), and other pests in the Everglades ranchers, businesses, and all levels of government to con- and southern Florida trol the economic, health, and environmental threats these • Supporting management efforts related to invasive weeds invaders pose. such as salt cedar (Tamarix spp.), cheatgrass (Bromus • Invasive species decrease agricultural production, com- tectorum), Russian olive (Elaeagnus angustifolia), leafy pete with and predate on native plants and wildlife, impair spurge (Euphorbia esula), brome (Bromus spp.), and critical water infrastructure, transmit disease to wildlife buffelgrass Cenchrus( ciliaris) and humans, threaten commercial and native fisheries, and • Assisting Federal, State and Tribal partners with response reduce hunting, fishing, and other recreational opportuni- to zebra and quagga mussels (Dreissena polymorpha and ties such as boating and swimming. D. bugensis) in the continental United States • Providing nationwide reporting, monitoring, and tracking of all freshwater aquatic invasive species as part of a national early detection system

U.S. Department of the Interior Fact Sheet 2018–3080 U.S. Geological Survey April 2019 USGS EMA Advanced Tools and Technology

Genetics and Invasive Species Detection—Environmental deoxyribonucleic acid (eDNA), genetic material shed by organisms into the waters in which they live, has recently emerged as a powerful genetic tool for detecting invasive species and rare aquatic animals in lake or river water. USGS research has led to refinements of methods to improve detection sensitivity, understand how eDNA changes over time, and decrease time between sampling and results. For example, scientists have developed a portable eDNA detection kit for detecting bighead and silver carps that provides results in less than an hour and could be used to detect other species. The USGS also used eDNA sampling to detect invasive northern pike (Esox lucius) in several south-central Alaska lakes following eradication efforts, and to monitor potential In Hawai’i, USGS scientists have developed a range expansion of pythons successful eDNA field method to detect the fungus and snakeheads in southern that causes Rapid Ohi’a Death (ROD) in mature Ohi’a Florida. trees in collaboration with partners.

Early Detection and Rapid Response (EDRR) Tool Development— While invasive species prevention is the first line of defense, even the best prevention efforts will not stop all invaders. EDRR is a coordinated set of actions to detect and eradicate potential invasive species in a specific location before they spread and cause harm. In one example, the USGS provides scientific support to resource managers to aid in implementation of EDRR efforts, make informed management actions, and lead multiagency and partner rapid response efforts such as training relative to brown treesnake (BTS) rapid response. For this effort, the USGS devel- Buffelgrass is a nonnative perennial oped a model for determining the amount of search and (or) trap effort required grass that is rapidly spreading across when responding to BTS rapid response efforts to meet the desired degree of cer- National Park Service (NPS) and tainty by resource managers that a population is not present in the area. adjacent lands in the Sonoran Desert in Arizona and California and can carry fire quickly across the landscape. USGS is working with the NPS and others on EDRR tools to detect invasive buffelgrass such as sensors aboard Unmanned Nonindigenous Aerial Systems and high-resolution Aquatic Species satellite imagery. Database—The USGS Nonindigenous Aquatic Species (NAS) Program, created by Congress in 1990 to provide timely information to natural resource managers, maintains a database that helps managers monitor, record, and analyze sightings of nonindigenous aquatic plant and animal species throughout the United States. The NAS database is a clearinghouse of information for confirmed sightings of nonindigenous aquatic species throughout the Nation. The database assists managers by sending email risk alerts intended to support prompt early detection and rapid response efforts in the field when new species are detected in sites of concern. Flood and Storm USGS scientists developed tools to assist managers in Tracker (FaST) Maps, a new NAS database product, enable predicting potential range expansions of invasive lionfish managers to predict potential spread of NAS associated with (Pterois volitans) following weather-related flooding such flooding and storm surge events. The database also provides as hurricanes, and in producing maps indicating potential species distribution maps, scientific publications, and other rapid response areas after a new location is invaded. information products to support natural resource management. USGS EMA Research Examples

Zebra and Quagga Mussels—Invasive zebra and quagga mussels (collectively called dreissenid mussels) affect industrial and municipal infrastructure, recreational water use, and they severely alter aquatic ecosystems as they spread across North America. The USGS has been conducting dreissenid mussel control and rapid response in the Great Lakes and Upper Mississippi River Basins for several years including developing genetic tools for detecting and evaluating the application of molluscicides and assessing effects on nontarget species. In 2016 the first detection of dreissenid mussel larvae was documented in Montana resulting in strengthened Federal government efforts, in coordination with States and Tribes, to address invasive mussels in the Northern Rocky Mountains and Columbia River Basin. In support of this effort, the USGS evaluated genetic mark- ers for early detection of Invasive zebra mussels are now part of many dreissenid mussels and is of our Nation’s lakes and rivers, and USGS working to improve eDNA science and technical assistance is assisting sampling and analysis pro- in the control and prevention of further spread tocols, and early-detection of these and other damaging mollusks. monitoring plans.

Asian Carps— High-density populations of Asian carps [bighead, black, grass, and silver carps (Hypophthalmichthys nobilis, Mylopha- ryngodon piceus, Ctenopharyngodon idella and H. molitrix)] have caused a range of negative impacts to the Nation’s waterways. The USGS provides data, tools, and technologies to partners to keep these invasive fish out of the Great Lakes and other aquatic ecosystems, and to control them where they occur in the Ohio and Mississippi River USGS has extensive capabilities that have led to develop- Basins. Current field testing is being conducted on underwater sound ment of the risk assessment tool, Fluvial Egg Drift Simulator, technology and carbon dioxide levels in water as methods to deter for bighead, silver, and grass carps to predict where Asian Asian carps range expansion, and researchers are testing a specific carps are likely to spawn and where eggs and larvae will toxicant to control populations in open-water systems. likely be located after spawning.

Brown Treesnakes and Pacific Islands Biosecurity Research— The BTS is a threat to the economy and unique ecosystems of Guam, specifi- cally to the biodiversity, economy, and human health of the Pacific region and beyond. The BTS was accidentally introduced to Guam in the late 1940s and has caused global or island-wide extinction of 9 of 13 native forest birds. This invader frequently short circuits power lines, causing costly power outages and is a significant biosecurity risk. The USGS has played an essential role in developing control techniques such as traps and barriers to manage this pest and leads the regional BTS Rapid Response Team to ensure effective EDRR to BTS sightings in new locations on the Pacific Islands. Scientists have also been applying lessons learned from working on the BTS to inform other biosecurity efforts regionally.

A brown treesnake crawls on some frangipangi blossoms in Guam, where significant quarantine efforts are implemented to prevent the introduction and establishment of this invasive snake elsewhere.

Burmese Pythons—Burmese pythons are large invasive snakes, which can exceed 18 feet and 150 pounds. USGS research on Burmese pythons has focused on methods for detection and control, predicting potential range of the species in the United States, understanding thermal tolerances, and conducting risk assessments of pythons and other giant constrictors. The USGS continues to conduct research to aid in the management of Burmese pythons in Everglades National Park, Big Cypress National Preserve, and other DOI lands in southern Florida. Recently, USGS scien- USGS scientists conduct research on tists and partners documented that Burmese pythons have devastated the mammal invasive Burmese pythons in Everglades communities in Everglades National Park and are known to have consumed several National Park and other DOI lands in endangered species including Wood Storks (Mycteria americana) and Key Largo South Florida to aid in the management of woodrats (Neotoma floridana smalli). these large, voracious constrictor snakes. Cheatgrass—Cheatgrass and other invasive grasses continue to expand into sagebrush ecosystems in western United States where they colonize burned areas before native plants can become established, providing more fuel for wildland fire. USGS scientists are assessing strategies to restore native vegetation to fight cheatgrass invasion and increase postfire resilience. These strategies include modeling postfire recovery times and developing fire management protocols that include alternatives to chemical and mechanical cheatgrass control methods and linking patterns of wildfire across the Great Basin with changing sage-grouse populations and climate. Invasive cheatgrass turning red in the Squirrel Creek burn area, Medicine Bow National Forest, Wyoming. The USGS developed a map of the percentage of cheatgrass cover by early June each year which can help land managers plan fire operations and protective measures for development and crucial wildlife habitats.

Salt Cedar (Tamarisk)—The USGS is a leader in understanding the distribution and impact of invasive salt cedar, known as tamarisk, on riparian ecosystems in the Southwest including effects on plant communities, water loss, erosion, wildlife use and human recreational resources. Scientists are studying the effectiveness of biological control to reduce salt cedar populations, in collaboration with multiple In arid and semiarid regions of the western partners to provide valuable information for resource managers tasked with United States, much of the riparian vegeta- decisions related to restoration of native plant communities and associated wildlife, tion is dominated by nonnative shrubs and assessments of changes in water yield. and trees such as salt cedar (tamarisk), which have replaced native vegetation in many areas over the past several decades. Sea (Photograph from NPS) Lamprey— The parasitic sea lamprey invaded the Great Lakes in the mid-20th century, devastating valuable native fisheries and coastal economies. The USGS plays a central role in sea lamprey control research by working with the Great Lakes Fishery Commission, the U.S. Fish and Wildlife Service, other State, Federal, and Tribal agencies, and academic institutions to provide science on sea lamprey biology, ecology, and control technologies. Recently, the USGS developed a novel trap and electrical guidance array capable of removing 75 percent of invasive sea lamprey from a stream with minimal impacts to nontarget species and streamflow. Sea lampreys feed on the blood and fluids of native fish, causing population declines in commercial and recreational species that are essential to the Great Lakes’ multibillion dollar per year fishery. USGS scientists registered with the U.S. Environmental Protection Agency the first vertebrate pheromone, which when applied can increase sea lamprey trap catch by 35 percent.

Black and White Tegu—(hereafter referred to as tegu) are large omnivorous lizards native to South America and are common in inter- national pet trade. There are at least three established populations of tegus in southern Florida, all likely resulting from escaped or released pets. Tegus eat a variety of plants and animals but specialized in consuming eggs from bird and reptile nests. USGS scientists recently demonstrated that conditions suitable for tegu survival may exist across the southern one-third of the continental United States. USGS research on tegus includes developing and testing methods for detec- USGS is working on development of tools for the detection and tion and control, determining thermal tolerances, and assessing risks capture of invasive reptiles in Florida such as black and white to the greater Everglades ecosystem. tegu lizards (Salvator merianae).

Contact Information Cindy Tam, Invasive Species and Disease Program Coordinator [email protected] or 703-648-4023 Photograph Credits ISSN 2327-6916 (print) Earl Campbell, Invasive Species Program Manager [email protected] or 703-648-5861 Tegu and zebra mussel images from ©iStock.com ISSN 2327-6932 (online) https://www.usgs.gov/ecosystems/invasive-species-program All other images are U.S. Geological Survey https://doi.org/10.3133/fs20183080